There are many different types of infant-feeding nipples available on the market, most of which must be attached directly to the container or bottle which supplies the liquid to the infant. In these conventional arrangements, the bottle must be elevated above the infant's mouth so that the liquid contained therein fills the nipple attached to the bottle in order to enable the infant to suck on the nipple and draw liquid from the bottle. In order for the infant itself to hold the bottle in a properly elevated position, the infant must generally have reached a certain stage of development and maturity. Moreover, the infant must generally be in a reclining position in order to properly orient the bottle for drinking from it. With such conventional systems, it is not uncommon for the bottle to be lowered from the properly elevated position, permitting the liquid to flow out of the nipple back into the bottle and resulting in the infant ingesting air when an effort is next made to drink from the bottle. This can lead to discomfort and/or frustration of the infant. Moreover, the necessity for holding a conventional bottle in an elevated position in close proximity to the infant's face prevents the infant from engaging in other activities or play while feeding, or requires the assistance of a parent or other attendant, or requires "propping" of the bottle to enable the infant to drink from the bottle while lying down.
Some specially constructed infant-feeding nipple systems have been developed in the prior art which enable an elongate conduit to be attached to the nipple at one end and to a container of liquid at the other end so that the infant can drink liquid from the container without holding the container in an elevated position in close proximity to the infant's face. However, such prior art systems are either relatively complex and expensive in construction, or are limited in their versatility of use. Moreover, such conventional systems may be difficult to clean and/or sterilize following use, and they do not include check valve means to prevent ingress of air into the nipple and conduit when sucking action ceases, whereby the liquid is enabled to flow out of the nipple and conduit, resulting in loss of prime of liquid in the nipple and conduit and ingestion of air by the infant when feeding is resumed.
Sometimes it may be desirable for a parent or other attendant to hold the infant while the infant is feeding, and in these circumstances a bottle may be held by the parent or the other attendant in a properly elevated position in close proximity to the infant's mouth. The parent or other attendant can ensure that the bottle is maintained in the proper position to avoid ingestion of air by the infant, which can otherwise lead to discomfort or frustration of the infant. At other times, however, it may not be convenient or even possible for a parent or other attendant to hold a bottle in a normal, properly elevated position for feeding the infant, and in these circumstances an infant-feeding system is required that does not necessitate holding the container of liquid in an elevated position in close proximity to the infant's mouth. This may occur, for example, when only one parent or other attendant is in company with the infant and is not able to hold the infant and/or the bottle in proper position for feeding in a conventional way, such as when the infant is secured in a car seat and the parent or other attendant is occupied with driving a vehicle or is engaged in other activity.
There is thus need for an infant-feeding nipple system that can be used to feed an infant conventionally, i.e., with the bottle held in elevated position and in close proximity to the infant's mouth, or which can be used in a variety of ways to enable the infant to drink liquid from a bottle that may not be held in an elevated position or even in close proximity to the infant's mouth, or even to drink from a container other than a bottle, such as a carton, soft drink can, glass, or other container. Further, there is need for such a device which is simple and economical in construction and easy to clean and sterilize, and which maintains the liquid in the nipple when suction action ceases.